Line boring bar assembly

ABSTRACT

Apparatus for line boring the bearing surfaces in an automobile engine block including means to accurately mount the said apparatus onto an engine block, means to accurately bore the main and reface the thrust bearing surfaces; automatic planetary transmission means for screw feeding the cutting heads mounted on the line boring bar at a constant speed during the boring, and means to rotate the said boring bar carrying the said cutting heads.

United States Patent [1 1 111 3,767,316 I Dumont, Jr. Oct. 23, 1973I541" LINE BORING BKF' ASSEMBLY 2,439,492 4 1948 Sharratt 408 114 x-2,964,978 12 1960 Alafouzos 408/79 [76] Inventor: Walter M. Dumont, Jr.,2919 I ,O l Wmlam S St Muskogee k a Primary ExaminerLeonidas Vlachos74401 AttorneyRalph E. Zimmerman [22] Filed: Sept. 20, 1972 [2]] App].No.: 290,540 [57] ABSTRACT Apparatus for line boring the bearingsurfaces in an 52 us. 01 408/79, 408/82, 408/83, automobile engine blockincluding means to accu- 408,115 rately mount the said apparatus onto anengine block, 51 1111.01 B23b 41 12 means to accurately bore the mainand reface the [58] Field of Search 408/42, 79, 72, 4, thrust bearingSurfaces; automatic Planetary transmis- 408/54, 80, 82, 83 114, 115 sionmeans for screw feeding the cutting heads mounted on the line boring barat a constant speed [56] References Cited during the boring, and meansto rotate the said boring UNITED STATES PATENTS bar carrymg the sa1dcutting heads.

1,434,004 10 1922 Graven 408 115 x 7 laim 7 Drawing Figures 2,401,838 61946 Mitchell 408 72 x 2 LINE BORING BAR ASSEMBLY BACKGROUND OF THEINVENTION In the operation of rebuilding automotive engines, it has beenfound that the present tools available for reboring main and refacingthrust bearing surfaces do not accurately align the boring tools withthe bearing surface each with each other especially in a Volkswagonengine. In order to reduce the vibration in the running motor and reducethe amount of uneven wear due to misalignment of the boring tool withthe bearing surfaces, I have invented a line boring bar assembly whichis readily adaptable for boring the surfaces of both the thrust and mainbearings. It has been found that my apparatus is adaptable for mountingto the block structure of the automobile engine with the exact alignmentof the cutting heads for resurfacing the main and thrust bearingsurfaces.

The main object of this invention is to disclose apparatus suitable foraccurately line boring the main and thrust bearing surfaces in anautomotive engine.

Another object of this invention is to disclose apparatus for accuratelysetting the cutting blades on the line boring bar.

Still another object of this invention is to disclose a method ofresurfacing both main and thrust bearing surfaces in an automotiveengine block.

SUMMARY OF THE INVENTION FIG. 1 is a top view showing the line boringassembly with micrometer means to set the cutting heads.

FIG. 2 is a perspective top view drawing showing the line boringassembly in operating position on an engine block with the adapter foraligning a center ring.

FIG. 3 is a perspective drawing looking down on the line boring machineassembled on an engine block with manual means to turn the assembly.FIG. 3a is a perspective drawing showing a partial view of the engineblock with the knocker attached to the centering ring of the boring barassembly. v

FIG. 4 is a perspective drawing showing the radial (thrust) bearingencasement with the radial (thrust) bearing cutting head in cuttingposition.

FIG. 5 is a perspective drawing showing the boring I bar in completeassembly for resurfacing the radial (thrust) bearing surface area.

FIG. 6 is a perspective drawing showing the position of the radial(thrust) cutting head, the centering ring and the split set collar onthe line boring bar assembled in an engine block.

DESCRIPTION 1 Referring now to FIG. 1 which shows the line boring bar inassembly. The automotive planetary 'gear screw feed 23 which is a l-7reduction automatically moves cutting heads 7, 7, 7", 7", mounted onboring bar 1 across the bearing surface in the engine block 13, FIG. 2.Boring bar 1 with cutting heads 7, 7', 7", 7" is supported by centeringring 5 mounted on the engine block at position 14, FIG. 2. The other endof the bo'ring bar 1 is supported in the engine block by dog leg 2,FIGS. 1 and 2, which is mounted on the opposite end of the motor block13 in an opening at position 15. At position 15 attached to the lowerend of dog leg 2 which is supported in the engine block 13 is rod 12(FIGS. 16) which extends throughout the motor block assembly 13 and issecured at the other end of the engine block assembly 13 by a washer anda wing nut mounted on rod 12. (See FIG. 2). Planetary gear automaticfeeding means 23 FIG. 1 is shown attached to the boring bar by mountingplate 18. (FIGS. 1 and 3). The planetary gear feeding means 23 issupported in cradle 3. (FIGS. 1 6). Cradle 3 is connected to the lowersection of dog leg 2 at position 15 FIG. 3, which in turn is supportedby rod 12 bolted through the motor block 13. Planetary gear feedingmeans 23 which has two separately moving section is held partiallystationary be elastic bands 19 (FIGS. 2 and 3) which causes the rotatingboring bar 1 with cutters heads 7, 7', 7", 7 mounted on boring rod 1 tomove across the surface of the main bearing surfaces at constant speedlocated beneath the cutter heads 7, 7, 7", 7" in the motor block 13.(See FIG. 2). The boring bar 1 is manually rotated by handle 11 which isattached to the end of the boring rod 1. (See FIG. 2).

Each of the cutting heads 7, 7', 7"and 7" is secured to the boring rodby set screws (not shown), carbide cutters for example 20, which are setin the cutting heads 7, 7,7, and 7" are adjusted by placing the boringbar 1 with cutting heads 7, 7', 7", and 7" respectively in the groove ofmicrometer stand 6, FIG. 1, the

micrometer being useful to gauge the cutting heads 7, 7', 7, 7 to thedesired bore size of the bearings. This is done by adjusting the cuttersto cut the correct size bore opening. I

Item 8, FIG. 1, is a radial (thrust) cutting head. Item 9, FIG. 1, is asplit set collar, the utility of which shall be explained later. Thesliding knocker 10, FIG. 3, is

- useful for properly seating the centering ring 5 into position on themotor block 13, FIG. 3. The sliding knocker 10 is bolted to thecentering ring 5 at bolts 16, FIG. 3a. 1

The boring bar assembly which I have disclosed herein has dual utilitynot only will it be useful in properly boring bearing surfaces, but italso has utility in properly facing the radial bearing surface, as shownin FIGS. 4, 5, and 6. FIG. 4 portrays the position of the radial bearingsurface cutting head 8 in position on the radial (thrust) bearingsurface 24. FIG. 6 shows the relationship of positioning of the radialsurface cutting head 8, centering ring 5 and split ring 9 on boring barOPERATION To obtain accurate results in usingthe boringbar disclosedherein, the boring bar 1 with cutting heads, 7,7, 7",7 attached must beset to the specific bore opening desired. This is accomplished byplacing the bar 1 with the cutting heads 7,7',7, and 7" in position inthe micrometerstand 6. The micrometer (4) reading is then set to thesetting desired. For instance to bore 0.020 oversize, the setting wouldbe 900;-0.040 oversize the setting would be 910, and for 0.060 oversize,the setting would be 920. When the desired setting is determined, eachof the cutting heads with carbide cutters 7,7,7", and 7" are set in thernicromter stand 6 FIG. 1 and adjusted to the proper cutting size.

The micrometer stand 6, FIG. 1, can bestbe described having a base 6with a groove for holding the boring bar 1 with the cutting head 7,7',7,and 7". attached in a measuring position. The micrometer 4 itself, whichis mounted on the side of the stand 6 is posi-v tioned so that accuratereading can be made and the carbide cutter adjusted by moving it in theslotted hole 20, FIG. 1, in the cutting heads 7,7,7",7", FIG. 1. thecarbide cutter is held in adjustment by a set screw (not shown) in eachof the respective cutting heads.

The boring bar 1 with the cutting heads 7,7',7", and 7" FIG. 1 withcarbide cutter properly set is placed in cutting position in the motorblock 13, FIG. 2. Dog leg 2 is placed in position as shown in FIG. 2,the lower section of dog leg 2 being secured in the oil hole opening 15of motor block 13 by rod 12, FIG. 1 passes rod 12 through the motorblock 13. Dog leg 2 is held in place by tightening the wing not over thewasher on rod 12. (See FIG. 2).

Cradle 3 with threaded adjustment screw 22 and adjustable nut 21 FIG. 1and planetary feed mechanism 23 are aligned in the cradle as shown inFIG. 1. Rubber bands 19 are placed over one section of the planetaryfeed mechanism 23 as shown in FIG. 1. Centering ring 5, FIG. 1, isplaced around the boring bar and fitted into the engine block 13 asshown in FIG. 2. Slide knocker 10 is bolted on the center ring to alignthe center ring 5 into position as shown in FIG. 3a by gently tappingthe centering ring 5 into place with knocker 10. The slide knocker isremoved and split collar 9 is positioned and secured around the boringbar 4 against the centering ring 5. Handle 11 is mounted on the boringbar 1 as shown in FIG. 5 for manual rotation of the boring bar 1. Handle11 is manually rotated moving the boring bar 1 in a clockwise direction.As the boring bar 1 is rotated, the operation of the planetary feedmechanism caused the cutting heads 7,7"',7"' with carbide cutting bladesto move inwardly axially across the bearing surfaces in engine block 13,FIG. 2. When the cutting heads 7,7,7", and 7" have completed theiraxially travel cutting head 7 is removed and thrust bearing surfacecutting head 8 is positioned on the boring bar in the thrust bearingwhen seated will be properly aligned with the main bearings in the motorblock 13, FIG. 4. When the thrust bearing surface cutting head 8 isplaced on the boring bar 1 it is taped tightly into position by placingthe centering ring 5 with the sliding knocker 10 attached thereto on theboring bar 1 as shown in FIG. 3a. The knocker 10 is gently taped fourtimes to proper place the centering ring 5 against the thrust bearingsurface cutting head 8. The knocker 10 is removed, split set collar 9 isadjusted and spaced to be taken on the bearing surface 14 from thecentering ring 5 to provide for amount of cut and them secured to theboring bar 1 with a set screw. The handle 11 is rotated until the thrustcutting head 8 has moved rotatively to release the cutting head 8 fromcontact with the thrust bearing surface 24, FIG. 4. At this time thehandle 11, the set collar 9, and the center ring 5 and the thrustbearing surface cutter 8 are removed from the boring bar 4 and theboring bar assembly removed from the motor block 13.

Although this disclosure shows manual operation, it should be understoodthat the boring bar assembly is adaptable to electrical drive means byadding a pulley with electrical motor means attached thereto.

I claim:

1. In a device for line boring the main and radial bearing surfaces inan engine block,

a. a first support means positioned on one side of the said engine blockfor supporting and centering a cylindrical boring bar in the said engineblock,

I. the said boring bar having at least one cutting head attachedthereto,

b. a second support means for supporting the said boring bar on theopposite side of the said engine block,

1. the said second support means being a cradle comprising a lowersupport member and a first and second upright support member,

2. means mounting and attaching said cradle to the said engine blockthrough an opening in the lower extremity of the said engine block,

3. means rotatably mounting said line boring bar in the said two uprightsupport members.

2. The device as claimed in claim 1 where the said first support meansis a cylindrical centering ring inserted into the upper side of the saidengine block.

3. The device as claimed in claim 1 where a handle is attached to theend of the boring bar to provide a means of manual rotation.

4. The device as claimed in claim wherein a planetary gear screw feedwith a first and second section is attached to the end of the saidboring bar, means to hold the said second section stationery while thesaid first section rotates.

5. The device as claimed in claim 1 wherein the said first uprightsupport member is a dog leg with means to secure the said dog leg to thesaid engine block, the said dog leg having collar means for the saidboring bar to rotate therein.

6. The device as claimed in claim 2 wherein the said centering ring hasmeans for attaching a knocker for aligning the said centering ring.

7. The device as claimed in claim 2 wherein a radial bearing surfacecutting head and a spacer are positioned on the boring bar within thesaid centering ring.

1. In a device for line boring the main and radial bearing surfaces inan engine block, a. a first support means positioned on one side of thesaid engine block for supporting and centering a cylindrical boring barin the said engine block,
 1. the said boring bar having at least onecutting head attached thereto, b. a second support means for supportingthe said boring bar on the opposite side of the said engine block, 1.the said second support means being a cradle comprising a lower supportmember and a first and second upright support member,
 2. means mountingand attaching said cradle to the said engine block through an opening inthe lower extremity of the said engine block,
 3. means rotatablymounting said line boring bar in the said two upright support members.2. The device as claimed in claim 1 where the said first support meansis a cylindrical centering ring inserted into the upper side of the saidengIne block.
 2. means mounting and attaching said cradle to the saidengine block through an opening in the lower extremity of the saidengine block,
 3. The device as claimed in claim 1 where a handle isattached to the end of the boring bar to provide a means of manualrotation.
 3. means rotatably mounting said line boring bar in the saidtwo upright support members.
 4. The device as claimed in claim 3 whereina planetary gear screw feed with a first and second section is attachedto the end of the said boring bar, means to hold the said second sectionstationery while the said first section rotates.
 5. The device asclaimed in claim 1 wherein the said first upright support member is adog leg with means to secure the said dog leg to the said engine block,the said dog leg having collar means for the said boring bar to rotatetherein.
 6. The device as claimed in claim 2 wherein the said centeringring has means for attaching a knocker for aligning the said centeringring.
 7. The device as claimed in claim 2 wherein a radial bearingsurface cutting head and a spacer are positioned on the boring barwithin the said centering ring.